When Marcin Wichary, the well-known past design lead and typographer of the blogging platform Medium, visited Japan for several weeks, he immediately took notice of the UI or “user interface” of Japanese life. The signs, buttons and general ways of doing things such as lining up for the train or purchasing a meal might be facts of life that Japanese people take for granted but are surprising to people from other parts of the world.

Over the course of his two-week stay in Japan, he starting using Twitter to document his observations about Japan's approach to everything from signage to trash receptacles. The result was a massive thread with 300 individual tweets that quickly went viral:

This epic thread of @mwichary‘s observations and surprising moments in Japan, with an emphasis on everyday UIs, is just the best. I wish this was a blog. https://t.co/L1hi2Qvlxt

As he live-blogged on Twitter, Wichary frequently asked for insights about the various phenomenon he encountered such as these signs notifying subway users how far above sea level the entrance is. (These signs are in case of tsunami — tsunami waves following the 2011 Tohoku earthquake towered over thirty meters above sea level in some places on Japan's northeastern coastline):

Keyboard mystery: I’ve seen a bunch of older Mac keyboards today (including the legendary black MacBook) where Control key is adorned with an extra pen icon. What is that all about? I have never seen this before. pic.twitter.com/kPgbIWecwD

46. Is there a name for this kind of esthetic? Is western text stretched thin in here (which I see very often) just to make the low information density slightly less unbearable? pic.twitter.com/xqFwhS9B8u

Like many visitors to Japan, Wichary was struck by the care taken in Japan to avoid disturbing others. For example, Wichary noted that construction worksites typically post a schedule to alert locals about when work will take place:

78. It seems that construction sites are supposed to tell you ahead about their work schedule for the week? Some of those displays are even electronic!

(I drew the complicated one on my trackpad. It says 解体工事: demolition work. February 4 is Sunday = no construction.) pic.twitter.com/aVUnNHaP2a